Restless Legs Syndrome
Information Page
Publications |
NINDS is part of the
National Institutes of
Health
See a list of all NINDS Disorders
Get Web page suited for printing
Email this to a friend or colleague
Request free mailed brochure
Síndrome de las Piernas Inquietas
Table of Contents (click to jump to sections)
What is restless legs?What is restless legs? Restless legs syndrome (RLS) is a neurological disorder characterized by unpleasant sensations in the legs and an uncontrollable
urge to move when at rest in an effort to relieve these feelings. RLS sensations are often described by people as burning,
creeping, tugging, or like insects crawling inside the legs. Often called paresthesias (abnormal sensations) or dysesthesias
(unpleasant abnormal sensations), the sensations range in severity from uncomfortable to irritating to painful.
The most distinctive or unusual aspect of the condition is that lying down and trying to relax activates the symptoms. As
a result, most people with RLS have difficulty falling asleep and staying asleep. Left untreated, the condition causes exhaustion
and daytime fatigue. Many people with RLS report that their job, personal relations, and activities of daily living are strongly
affected as a result of their exhaustion. They are often unable to concentrate, have impaired memory, or fail to accomplish
daily tasks.
Some researchers estimate that RLS affects as many as 12 million Americans. However, others estimate a much higher occurrence
because RLS is thought to be underdiagnosed and, in some cases, misdiagnosed. Some people with RLS will not seek medical attention,
believing that they will not be taken seriously, that their symptoms are too mild, or that their condition is not treatable.
Some physicians wrongly attribute the symptoms to nervousness, insomnia, stress, arthritis, muscle cramps, or aging.
RLS occurs in both genders, although the incidence may be slightly higher in women. Although the syndrome may begin at any
age, even as early as infancy, most patients who are severely affected are middle-aged or older. In addition, the severity
of the disorder appears to increase with age. Older patients experience symptoms more frequently and for longer periods of
time.
More than 80 percent of people with RLS also experience a more common condition known as periodic limb movement disorder (PLMD).
PLMD is characterized by involuntary leg twitching or jerking movements during sleep that typically occur every 10 to 60 seconds,
sometimes throughout the night. The symptoms cause repeated awakening and severely disrupted sleep. Unlike RLS, the movements
caused by PLMD are involuntary-people have no control over them. Although many patients with RLS also develop PLMD, most people
with PLMD do not experience RLS. Like RLS, the cause of PLMD is unknown.
What are common signs and symptoms of restless legs? As described above, people with RLS feel uncomfortable sensations in their legs, especially when sitting or lying down, accompanied
by an irresistible urge to move about. These sensations usually occur deep inside the leg, between the knee and ankle; more
rarely, they occur in the feet, thighs, arms, and hands. Although the sensations can occur on just one side of the body, they
most often affect both sides.
Because moving the legs (or other affected parts of the body) relieves the discomfort, people with RLS often keep their legs
in motion to minimize or prevent the sensations. They may pace the floor, constantly move their legs while sitting, and toss
and turn in bed.
Most people find the symptoms to be less noticeable during the day and more pronounced in the evening or at night, especially
during the onset of sleep. For many people, the symptoms disappear by early morning, allowing for more refreshing sleep at
that time. Other triggering situations are periods of inactivity such as long car trips, sitting in a movie theater, long-distance
flights, immobilization in a cast, or relaxation exercises.
The symptoms of RLS vary in severity and duration from person to person. Mild RLS occurs episodically, with only mild disruption
of sleep onset, and causes little distress. In moderately severe cases, symptoms occur only once or twice a week but result
in significant delay of sleep onset, with some disruption of daytime function. In severe cases of RLS, the symptoms occur
more than twice a week and result in burdensome interruption of sleep and impairment of daytime function.
Symptoms may begin at any stage of life, although the disorder is more common with increasing age. Sometimes people will experience
spontaneous improvement over a period of weeks or months. Although rare, spontaneous improvement over a period of years also
can occur. If these improvements occur, it is usually during the early stages of the disorder. In general, however, symptoms
become more severe over time.
People who have both RLS and an associated condition tend to develop more severe symptoms rapidly. In contrast, those whose
RLS is not related to any other medical condition and whose onset is at an early age show a very slow progression of the disorder
and many years may pass before symptoms occur regularly.
What causes restless legs syndrome? In most cases, the cause of RLS is unknown (referred to as idiopathic). A family history of the condition is seen in approximately
50 percent of such cases, suggesting a genetic form of the disorder. People with familial RLS tend to be younger when symptoms
start and have a slower progression of the condition.
In other cases, RLS appears to be related to the following factors or conditions, although researchers do not yet know if
these factors actually cause RLS.
Researchers also have found that caffeine, alcohol, and tobacco may aggravate or trigger symptoms in patients who are predisposed
to develop RLS. Some studies have shown that a reduction or complete elimination of such substances may relieve symptoms,
although it remains unclear whether elimination of such substances can prevent RLS symptoms from occurring at all.
How is restless legs syndrome diagnosed? Currently, there is no single diagnostic test for RLS. The disorder is diagnosed clinically by evaluating the patient's history
and symptoms. Despite a clear description of clinical features, the condition is often misdiagnosed or underdiagnosed. In
1995, the International Restless Legs Syndrome Study Group identified four basic criteria for diagnosing RLS: (1) a desire
to move the limbs, often associated with paresthesias or dysesthesias, (2) symptoms that are worse or present only during
rest and are partially or temporarily relieved by activity, (3) motor restlessness, and (4) nocturnal worsening of symptoms.
Although about 80 percent of those with RLS also experience PLMD, it is not necessary for a diagnosis of RLS. In more severe
cases, patients may experience dyskinesia (uncontrolled, often continuous movements) while awake, and some experience symptoms
in one or both of their arms as well as their legs. Most people with RLS have sleep disturbances, largely because of the limb
discomfort and jerking. The result is excessive daytime sleepiness and fatigue.
Despite these efforts to establish standard criteria, the clinical diagnosis of RLS is difficult to make. Physicians must
rely largely on patients' descriptions of symptoms and information from their medical history, including past medical problems,
family history, and current medications. Patients may be asked about frequency, duration, and intensity of symptoms as well
as their tendency toward daytime sleep patterns and sleepiness, disturbance of sleep, or daytime function. If a patient's
history is suggestive of RLS, laboratory tests may be performed to rule out other conditions and support the diagnosis of
RLS. Blood tests to exclude anemia, decreased iron stores, diabetes, and renal dysfunction should be performed. Electromyography
and nerve conduction studies may also be recommended to measure electrical activity in muscles and nerves, and Doppler sonography
may be used to evaluate muscle activity in the legs. Such tests can document any accompanying damage or disease in nerves
and nerve roots (such as peripheral neuropathy and radiculopathy) or other leg-related movement disorders. Negative results
from tests may indicate that the diagnosis is RLS. In some cases, sleep studies such as polysomnography (a test that records
the patient's brain waves, heartbeat, and breathing during an entire night) are undertaken to identify the presence of PLMD.
The diagnosis is especially difficult with children because the physician relies heavily on the patient's explanations of
symptoms, which, given the nature of the symptoms of RLS, can be difficult for a child to describe. The syndrome can sometimes
be misdiagnosed as "growing pains" or attention deficit disorder.
How is restless legs syndrome treated? Although movement brings relief to those with RLS, it is generally only temporary. However, RLS can be controlled by finding
any possible underlying disorder. Often, treating the associated medical condition, such as peripheral neuropathy or diabetes,
will alleviate many symptoms. For patients with idiopathic RLS, treatment is directed toward relieving symptoms.
For those with mild to moderate symptoms, prevention is key, and many physicians suggest certain lifestyle changes and activities
to reduce or eliminate symptoms. Decreased use of caffeine, alcohol, and tobacco may provide some relief. Physicians may suggest
that certain individuals take supplements to correct deficiencies in iron, folate, and magnesium. Studies also have shown
that maintaining a regular sleep pattern can reduce symptoms. Some individuals, finding that RLS symptoms are minimized in
the early morning, change their sleep patterns. Others have found that a program of regular moderate exercise helps them sleep
better; on the other hand, excessive exercise has been reported by some patients to aggravate RLS symptoms. Taking a hot bath,
massaging the legs, or using a heating pad or ice pack can help relieve symptoms in some patients. Although many patients
find some relief with such measures, rarely do these efforts completely eliminate symptoms
Physicians also may suggest a variety of medications to treat RLS. Generally, physicians choose from dopaminergics, benzodiazepines
(central nervous system depressants), opioids, and anticonvulsants. Dopaminergic agents, largely used to treat Parkinson's
disease, have been shown to reduce RLS symptoms and PLMD and are considered the initial treatment of choice. Good short-term
results of treatment with levodopa plus carbidopa have been reported, although most patients eventually will develop augmentation,
meaning that symptoms are reduced at night but begin to develop earlier in the day than usual. Dopamine agonists such as pergolide
mesylate, pramipexole, and ropinirole hydrochloride may be effective in some patients and are less likely to cause augmentation.
In 2005, ropinirole became the only drug approved by the U.S. Food and Drug Administration specifically for the treatment
of moderate to severe RLS. The drug was first approved in 1997 for patients with Parkinson’s disease.
Benzodiazepines (such as clonazepam and diazepam) may be prescribed for patients who have mild or intermittent symptoms. These
drugs help patients obtain a more restful sleep but they do not fully alleviate RLS symptoms and can cause daytime sleepiness.
Because these depressants also may induce or aggravate sleep apnea in some cases, they should not be used in people with this
condition.
For more severe symptoms, opioids such as codeine, propoxyphene, or oxycodone may be prescribed for their ability to induce
relaxation and diminish pain. Side effects include dizziness, nausea, vomiting, and the risk of addiction.
Anticonvulsants such as carbamazepine and gabapentin are also useful for some patients, as they decrease the sensory disturbances
(creeping and crawling sensations). Dizziness, fatigue, and sleepiness are among the possible side effects.
Unfortunately, no one drug is effective for everyone with RLS. What may be helpful to one individual may actually worsen symptoms
for another. In addition, medications taken regularly may lose their effect, making it necessary to change medications periodically.
What is the prognosis of people with restless legs? RLS is generally a lifelong condition for which there is no cure. Symptoms may gradually worsen with age, though more slowly
for those with the idiopathic form of RLS than for patients who also suffer from an associated medical condition. Nevertheless,
current therapies can control the disorder, minimizing symptoms and increasing periods of restful sleep. In addition, some
patients have remissions, periods in which symptoms decrease or disappear for days, weeks, or months, although symptoms usually
eventually reappear. A diagnosis of RLS does not indicate the onset of another neurological disease.
What research is being done? Within the Federal Government, the National Institute of Neurological Disorders and Stroke (NINDS), one of the National Institutes
of Health, has primary responsibility for conducting and supporting research on RLS. The goal of this research is to increase
scientific understanding of RLS, find improved methods of diagnosing and treating the syndrome, and discover ways to prevent
it.
NINDS-supported researchers are investigating the possible role of dopamine function in RLS. Dopamine is a chemical messenger
responsible for transmitting signals between one area of the brain, the substantia nigra, and the next relay station of the
brain, the corpus striatum, to produce smooth, purposeful muscle activity. Researchers suspect that impaired transmission
of dopamine signals may play a role in RLS. Additional research should provide new information about how RLS occurs and may
help investigators identify more successful treatment options.
The NINDS sponsored a workshop on dopamine in 1999 to help plan a course for future research on disorders such as RLS and
recommend ways to advance and encourage research in this field. Participants' recommendations for further research included
the development of an animal model of RLS; additional genetic, epidemiologic, and pathophysiologic investigations of RLS;
efforts to define genetic and non-genetic forms of RLS; establishment of a brain tissue bank to aid investigators; continuing
investigations on dopamine and RLS; and studies of PLMD as it relates to RLS.
Research on pallidotomy, a surgical procedure in which a portion of the brain called the globus pallidus is lesioned, may
contribute to a greater understanding of the pathophysiology of RLS and may lead to a possible treatment. A recent study by
NINDS-funded researchers showed that a patient with RLS and Parkinson's disease benefited from a pallidotomy and obtained
relief from the limb discomfort caused by RLS. Additional research must be conducted to duplicate these results in other patients
and to learn whether pallidotomy would be effective in RLS patients who do not also have Parkinson's disease.
In other related research, NINDS scientists are conducting studies with patients to better understand the physiological mechanisms
of PLMD associated with RLS.
For more information on neurological disorders or research programs funded by the National Institute of Neurological Disorders and Stroke, contact the Institute's Brain Resources and Information Network (BRAIN) at:
BRAIN
P.O. Box 5801
Bethesda, MD 20824
(800) 352-9424
http://www.ninds.nih.gov
Information also is available from the following organizations:
Restless Legs Syndrome Foundation 1610 14th St NW Rochester, MN 55901-0229 Suite 300 Rochester, MN 55902-2985 rlsfoundation@rls.org http://www.rls.org Tel: 507-287-6465 Fax: 507-287-6312 |
National Sleep Foundation 1522 K Street NW Suite 500 Washington, DC 20005 nsf@sleepfoundation.org http://www.sleepfoundation.org Tel: 202-347-3472 Fax: 202-347-3472 |
WE MOVE (Worldwide Education & Awareness for Movement Disorders) 204 West 84th Street New York, NY 10024 wemove@wemove.org http://www.wemove.org Tel: 212-875-8312 Fax: 212-875-8389 |
National Organization for Rare Disorders (NORD) P.O. Box 1968 (55 Kenosia Avenue) Danbury, CT 06813-1968 orphan@rarediseases.org http://www.rarediseases.org Tel: 203-744-0100 Voice Mail 800-999-NORD (6673) Fax: 203-798-2291 |
NIH Publication No. 01-4847
Back to Restless Legs Syndrome Information Page
See a list of all NINDS Disorders
Prepared by:
Office of Communications and Public Liaison
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892
NINDS health-related material is provided for information purposes only and does not necessarily represent endorsement by or an official position of the National Institute of Neurological Disorders and Stroke or any other Federal agency. Advice on the treatment or care of an individual patient should be obtained through consultation with a physician who has examined that patient or is familiar with that patient's medical history.
All NINDS-prepared information is in the public domain and may be freely copied. Credit to the NINDS or the NIH is appreciated.
Last updated December 11, 2007